<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>jQuery动态粒子效果</title>
		<script src="https://cdn.staticfile.org/jquery/1.10.2/jquery.min.js"></script>
		<style type="text/css">
			html,
			body {
				width: 100%;
				height: 100%;
				margin: 0;
				padding: 0;
				overflow: hidden;
			}

			.container {
				width: 100％;
				height: 100%;
				margin: 0;
				padding: 0;
				background-color: #000000;
			}
		</style>
	</head>
	<body>
		<div id="jsi-particle-container" class="container"></div>
	</body>
</html>
<script type="text/javascript">
	var RENDERER = {
		PARTICLE_COUNT: 1000,
		PARTICLE_RADIUS: 1,
		MAX_ROTATION_ANGLE: Math.PI / 60,
		TRANSLATION_COUNT: 500,

		init: function(strategy) {
			this.setParameters(strategy);
			this.createParticles();
			this.setupFigure();
			this.reconstructMethod();
			this.bindEvent();
			this.drawFigure();
		},
		setParameters: function(strategy) {
			this.$window = $(window);

			this.$container = $('#jsi-particle-container');
			this.width = this.$container.width();
			this.height = this.$container.height();

			this.$canvas = $('<canvas />').attr({
				width: this.width,
				height: this.height
			}).appendTo(this.$container);
			this.context = this.$canvas.get(0).getContext('2d');

			this.center = {
				x: this.width / 2,
				y: this.height / 2
			};

			this.rotationX = this.MAX_ROTATION_ANGLE;
			this.rotationY = this.MAX_ROTATION_ANGLE;
			this.strategyIndex = 0;
			this.translationCount = 0;
			this.theta = 0;

			this.strategies = strategy.getStrategies();
			this.particles = [];
		},
		createParticles: function() {
			for (var i = 0; i < this.PARTICLE_COUNT; i++) {
				this.particles.push(new PARTICLE(this.center));
			}
		},
		reconstructMethod: function() {
			this.setupFigure = this.setupFigure.bind(this);
			this.drawFigure = this.drawFigure.bind(this);
			this.changeAngle = this.changeAngle.bind(this);
		},
		bindEvent: function() {
			this.$container.on('click', this.setupFigure);
			this.$container.on('mousemove', this.changeAngle);
		},
		changeAngle: function(event) {
			var offset = this.$container.offset(),
				x = event.clientX - offset.left + this.$window.scrollLeft(),
				y = event.clientY - offset.top + this.$window.scrollTop();

			this.rotationX = (this.center.y - y) / this.center.y * this.MAX_ROTATION_ANGLE;
			this.rotationY = (this.center.x - x) / this.center.x * this.MAX_ROTATION_ANGLE;
		},
		setupFigure: function() {
			for (var i = 0, length = this.particles.length; i < length; i++) {
				this.particles[i].setAxis(this.strategies[this.strategyIndex]());
			}
			if (++this.strategyIndex == this.strategies.length) {
				this.strategyIndex = 0;
			}
			this.translationCount = 0;
		},
		drawFigure: function() {
			requestAnimationFrame(this.drawFigure);

			this.context.fillStyle = 'rgba(0, 0, 0, 0.2)';
			this.context.fillRect(0, 0, this.width, this.height);

			for (var i = 0, length = this.particles.length; i < length; i++) {
				var axis = this.particles[i].getAxis2D(this.theta);

				this.context.beginPath();
				this.context.fillStyle = axis.color;
				this.context.arc(axis.x, axis.y, this.PARTICLE_RADIUS, 0, Math.PI * 2, false);
				this.context.fill();
			}
			this.theta++;
			this.theta %= 360;

			for (var i = 0, length = this.particles.length; i < length; i++) {
				this.particles[i].rotateX(this.rotationX);
				this.particles[i].rotateY(this.rotationY);
			}
			this.translationCount++;
			this.translationCount %= this.TRANSLATION_COUNT;

			if (this.translationCount == 0) {
				this.setupFigure();
			}
		}
	};
	var STRATEGY = {
		SCATTER_RADIUS: 150,
		CONE_ASPECT_RATIO: 1.5,
		RING_COUNT: 5,

		getStrategies: function() {
			var strategies = [];

			for (var i in this) {
				if (this[i] == arguments.callee || typeof this[i] != 'function') {
					continue;
				}
				strategies.push(this[i].bind(this));
			}
			return strategies;
		},
		createSphere: function() {
			var cosTheta = Math.random() * 2 - 1,
				sinTheta = Math.sqrt(1 - cosTheta * cosTheta),
				phi = Math.random() * 2 * Math.PI;

			return {
				x: this.SCATTER_RADIUS * sinTheta * Math.cos(phi),
				y: this.SCATTER_RADIUS * sinTheta * Math.sin(phi),
				z: this.SCATTER_RADIUS * cosTheta,
				hue: Math.round(phi / Math.PI * 30)
			};
		},
		createTorus: function() {
			var theta = Math.random() * Math.PI * 2,
				x = this.SCATTER_RADIUS + this.SCATTER_RADIUS / 6 * Math.cos(theta),
				y = this.SCATTER_RADIUS / 6 * Math.sin(theta),
				phi = Math.random() * Math.PI * 2;

			return {
				x: x * Math.cos(phi),
				y: y,
				z: x * Math.sin(phi),
				hue: Math.round(phi / Math.PI * 30)
			};
		},
		createCone: function() {
			var status = Math.random() > 1 / 3,
				x,
				y,
				phi = Math.random() * Math.PI * 2,
				rate = Math.tan(30 / 180 * Math.PI) / this.CONE_ASPECT_RATIO;

			if (status) {
				y = this.SCATTER_RADIUS * (1 - Math.random() * 2);
				x = (this.SCATTER_RADIUS - y) * rate;
			} else {
				y = -this.SCATTER_RADIUS;
				x = this.SCATTER_RADIUS * 2 * rate * Math.random();
			}
			return {
				x: x * Math.cos(phi),
				y: y,
				z: x * Math.sin(phi),
				hue: Math.round(phi / Math.PI * 30)
			};
		},
		createVase: function() {
			var theta = Math.random() * Math.PI,
				x = Math.abs(this.SCATTER_RADIUS * Math.cos(theta) / 2) + this.SCATTER_RADIUS / 8,
				y = this.SCATTER_RADIUS * Math.cos(theta) * 1.2,
				phi = Math.random() * Math.PI * 2;

			return {
				x: x * Math.cos(phi),
				y: y,
				z: x * Math.sin(phi),
				hue: Math.round(phi / Math.PI * 30)
			};
		}
	};
	var PARTICLE = function(center) {
		this.center = center;
		this.init();
	};
	PARTICLE.prototype = {
		SPRING: 0.01,
		FRICTION: 0.9,
		FOCUS_POSITION: 300,
		COLOR: 'hsl(%hue, 100%, 70%)',

		init: function() {
			this.x = 0;
			this.y = 0;
			this.z = 0;
			this.vx = 0;
			this.vy = 0;
			this.vz = 0;
			this.color;
		},
		setAxis: function(axis) {
			this.translating = true;
			this.nextX = axis.x;
			this.nextY = axis.y;
			this.nextZ = axis.z;
			this.hue = axis.hue;
		},
		rotateX: function(angle) {
			var sin = Math.sin(angle),
				cos = Math.cos(angle),
				nextY = this.nextY * cos - this.nextZ * sin,
				nextZ = this.nextZ * cos + this.nextY * sin,
				y = this.y * cos - this.z * sin,
				z = this.z * cos + this.y * sin;

			this.nextY = nextY;
			this.nextZ = nextZ;
			this.y = y;
			this.z = z;
		},
		rotateY: function(angle) {
			var sin = Math.sin(angle),
				cos = Math.cos(angle),
				nextX = this.nextX * cos - this.nextZ * sin,
				nextZ = this.nextZ * cos + this.nextX * sin,
				x = this.x * cos - this.z * sin,
				z = this.z * cos + this.x * sin;

			this.nextX = nextX;
			this.nextZ = nextZ;
			this.x = x;
			this.z = z;
		},
		rotateZ: function(angle) {
			var sin = Math.sin(angle),
				cos = Math.cos(angle),
				nextX = this.nextX * cos - this.nextY * sin,
				nextY = this.nextY * cos + this.nextX * sin,
				x = this.x * cos - this.y * sin,
				y = this.y * cos + this.x * sin;

			this.nextX = nextX;
			this.nextY = nextY;
			this.x = x;
			this.y = y;
		},
		getAxis3D: function() {
			this.vx += (this.nextX - this.x) * this.SPRING;
			this.vy += (this.nextY - this.y) * this.SPRING;
			this.vz += (this.nextZ - this.z) * this.SPRING;

			this.vx *= this.FRICTION;
			this.vy *= this.FRICTION;
			this.vz *= this.FRICTION;

			this.x += this.vx;
			this.y += this.vy;
			this.z += this.vz;

			return {
				x: this.x,
				y: this.y,
				z: this.z
			};
		},
		getAxis2D: function(theta) {
			var axis = this.getAxis3D(),
				scale = this.FOCUS_POSITION / (this.FOCUS_POSITION + axis.z);

			return {
				x: this.center.x + axis.x * scale,
				y: this.center.y - axis.y * scale,
				color: this.COLOR.replace('%hue', this.hue + theta)
			};
		}
	};
	$(function() {
		RENDERER.init(STRATEGY);
	});
</script>
